Publication Date:
2017-04-04
Description:
Intense explosive activity occurred repeatedly
at Vesuvius during the nearly 1,600-year period between
the two Plinian eruptions of Avellino (3.5 ka) and Pompeii
(79 A.D.). By correlating stratigraphic sections from
more than 40 sites around the volcano, we identify the
deposits of six main eruptions (AP1–AP6) and of some
minor intervening events. Several deposits can be traced
up to 20 km from the vent. Their stratigraphic and dispersal
features suggest the prevalence of two main contrasting
eruptive styles, each involving a complex relationship
between magmatic and phreatomagmatic phases.
The two main eruption styles are (1) sub-Plinian to
phreato-Plinian events (AP1 and AP2 members), where
deposits consist of pumice and scoria fall layers alternating
with fine-grained, vesiculated, accretionary lapillibearing
ashes; and (2) mixed, violent Strombolian to
Vulcanian events (AP3–AP6 members), which deposited
a complex sequence of fallout, massive to thinly stratified,
scoria-bearing lapilli layers and fine ash beds. Morphology
and density variations of the juvenile fragments
confirm the important role played by magma–water interaction
in the eruptive dynamics. The mean composition
of the ejected material changes with time, and shows
a strong correlation with vent position and eruption style.
The ranges of intensity and magnitude of these events,
derived by estimations of peak column height and volume
of the ejecta, are significantly smaller than the values
for the better known Plinian and sub-Plinian eruptions
of Vesuvius, enlarging the spectrum of the possible
eruptive scenarios at Vesuvius, useful in the assessment
of its potential hazard.
Description:
Gruppo Nazionale
di Vulcanologia (GNV) of the Consiglio Nazionale delle
Ricerche (CNR) of Italy
Description:
Published
Description:
372-391
Description:
3.5. Geologia e storia dei sistemi vulcanici
Description:
JCR Journal
Description:
reserved
Keywords:
Avellino eruptions
;
Mount Vesuvius
;
Pompeii eruptions
;
Tephrostratigraphy
;
Volcanic hazards
;
05. General::05.02. Data dissemination::05.02.03. Volcanic eruptions
Repository Name:
Istituto Nazionale di Geofisica e Vulcanologia (INGV)
Type:
article
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